Ripper tooth



M. BRODERSEN 1,927,813

RIPPER TOOTH Filed Aug. 17, 1932 Inventor WWW ' A Homey J Patented Sept.26, 1933 PATENT OFFICE RIPPER TOOTH Max M. Brodersen, Los Angeles, Califassignor to Killefer Manufacturing Corporation, Ltd., Los Angeles,Calii'., a corporation of California Application August 17, 1932.

Serial No. 629,141

18 Claims. (01. 282-43) This invention relates to earth working toolsand in particular to a digging tooth for use in earth, rock, andespecially road working tools, so constructed as to produce such a toolas will 5 maintain its efllciency and working angles as the tooth wearsaway in use.

In one particular, it consists in the manner of distribution ofextremely hard abrasive resistant material upon a certain cross sectionof tooth. The portion of the tooth which serves to penetrate thematerial initially is so, constructed as to retain a minimum area wellsupported in the direction of maximum stress. In addition, that portionof the tooth serving to displace and break up the material is likewiseprovided with the same type of abrasive resistant material, distributedin such a manner as to provide penetrating points along the cleavageplanes which have been found to be most eflicient in breaking out suchmaterial with minimum power. Further, this abrasive resistant materialis placed in such a manner that under normal use the wear of the toothwill take place in a way that will maintain these penetrating points inpractically constant relation to each other and to the body portion ofthe tooth. In this manner an ideal cutting edge is maintained, and thelip angle, clearance, and back slope of the lip surface, likewisemaintain their relations automatically as the tooth wears in service.

In road working tools in particular, such as for example: rippers, it isextremely important that these elements of the tooth remain at all timesin correct relation to the material being worked. In such tools,efficiency is secured only by a correctly balanced relation between thedirection of travel of the tooth, the working depth, the power applied,the resultant working forces on the tooth, and the manner in which thematerial being worked breaks out. Such a correct balance is secured onlywhen the tooth angles are maintained in definite relation, as will belater described in the specification.

Broadly, the object of this invention is to produce a digging tooth ofmaterials having different physical properties so distributed relativeto the working angles and faces of the tooth and its normal positionduring use, as to maintain substantially the initial relation after longperiods of use, and the consequent abrading away of the materials at thesoil contact surfaces.

A further object of the invention is to produce a digging tooth whereinundesirable properties of one material are compensated by correspondingproperties of the other, whereby the tooth as a whole will giveunusually long and satisfactory service with maximum economy in the useof the materials of high cost.

Other objects will be apparent from the reading of the specification andthe advantages pointed out therein.

While the drawing shows, and the specification describes, but one formof the invention, it is obvious that many changes may be made withoutdeparting from the broad invention as distinctly pointed out in theclaims.

In the drawing:

Figure 1 is a side elevation of a tooth constructed in accordance withmy inventions-partially in section;

Figure 2 is a top view thereof Figure 3 is a section taken on line 33 ofFigure 1;

Figure 4 is a side elevation of the tool illustrated in working positionin the soil and also showing the tool as it appears after a period ofuse.

Figure 5 is a fragmentary perspective view of the working end of thetooth;

Figure 6 illustrates the type of wear which takes place in the ordinaryform of digger tooth;

Figure 7 shows the tooth of Figure 1 mounted oppositely on the shankfrom the mounting shown in Figure 4, such as may be used for moreshallow ripping, scarifying and other uses where the lifting action isnot predominant.

As illustrated, the tooth comprises a body 10, preferably of cast orforged steel, having a socketed upper end 11, for reception of the shank12, and provided with lateral openings 13 for the reception of boltheads 14, by which it is retained upon the shank 12. The shank 12 isattached to a wheeled carriage (not shown) by which it is supported.Opening 13a is provided for the escape of dirt from the socket. Theworking end 15 of the body is substantiallyof prismatic form with itssection substantially triangular, but for purposes of support for thehard facing material, the edges 16 are somewhat flattened. In practice,the form is obtained from a basic circle inscribing the edges 16 and thetop rib 17, between which flutes 16a are formed. The rib 17 serves tostrengthen the tooth and to split up the material displaced, minimizingthe tractive effort required to pull the tool. Smaller grooves 18 arealso formed in the edges 16 for the reception of wear resistant material19, such as tungsten carbide, other carbides of similar properties, orother hard compounds such as are known by the various trade names ofStellite, Stoodite, Hastellite.

These materials may be laid in the grooves in stick or granular form andappropriately bonded to the body material by welding, or may be embeddedlocally molten in the body material without the preforming oi thegrooves. The grooves may be filled with such material in the form ofwelding or facing rods, or a bead of such material may be welded on theedge, all processes well known in the welding art.

As arranged for attachment to its shank 1,4,.

in one arrangement the triangular section of the body 15 is so orientedas to provide a bottom edge 20, and two side edges 21. The bottom edge20, forms what may be called the hel" of the tooth. The working face, orlip surface, 22 is formed diagonally across the section extending fromthe bottom edge 20, rearwardlyupward, forming an acute angle designatedas the flip angle" with the bottom edge. As supported in workingposition, the heel or bottom edge 20 will extend rearwardly upward at asmall angle to the horizontal. The working face 22 extends rearwardlyupward at a much greater angle with the horizontal with the bottom edge20 intersecting the working face 22 at a point 23 in the positionillustrated considerably in advance of the intersections 24 of the sideedges 21 with the working face 22.

It will be seen that when such a tool is drawn along in the ground, theprojecting point 23 will horizontally penetrate the soil breaking itupwardly toward the surface over the surface 22. The force of this,action will be exerted through the shank l4 and carriage of the tool tothe drawbar in accordance with the proportioning and linkage of theconnecting framework, location of the wheels, and the angle of theworking face.

If the angle of the face is materially changed, the magnitude anddirection of the balancing forces must likewise change, and either thetool will tend to dig deeper imposing a greater load on the wheels, orwill tend to climb out, or to swing backward or forward changing thebreaking out angle of the soil, and resulting in less eincient actionthan that for which the tool angle is initially set.

Figure 6 illustrates the manner in which an ordinary pointed tool willwear away. The original point 25 unsupported by harder materialsextending along it even though it may be faced with such materials, Willbreak or wear away. This will leave such a point as 25a and often a heelor riding edge 26 sloped upwardly from the horizontal. Such a heel willproduce a downward wedging component on the formation consuming excesstractive effort and imposing heavy pressure against the point increasingthe wear thereon. a a

A tooth constructed in accordance with this invention is protected bythe wear resistant materials against creating such a poor shape ofdigging tooth as just described. The wearing away of the softer materialof which the body is formed will normally leave projecting points of theharder materials. These points will give the penetrating action requiredto crack the formation ahead. As the wear resistant material forms theouter edges of the tool, the tool will maintain its form and anytendency to wedge formation, either laterally or vertically is eithercompletely resisted, or speedily corrected by the wearing away of thesofter body material.

It will also be apparent that the wear resistant material extendingparallel to the body surfaces extends into said forward face, and inwhich adsurface of the top rib 17 may also be protected with a bead ofwear resistant material, but such has not been found tobe necessaryinmost c'ases owing to the efficient maintenance of the lip surface,and, in fact, may actually be undesirable.

When used as in Figure 7, the heel 20 forms a leading cutting edge,serving to spread the material upwardly and outwardly, splitting thematerial, rather than lifting it bodily as is the case when the tool isused in the manner shown in: Figure 4. In the claims, the parts andrelations of the tooth will be referred to as shown in position a forthe purposes of definition and reference only, but it will be understoodthat the claims are to be considered as equally applicable to the partswhen reversed in function and relation as. shown in Figure 7; andwithout limitation as to the position of use.

Having thus described one embodiment of my invention, I claim and desireto secure by Letters Patent:

l. A digger tooth including a body of substantially triangular sectionand prismatic form, the lateral edges thereof containing material havinggreater resistance to abrasion than the material of said body.

2. A digger tooth including a body having an earth lifting face, saidbody extending rearwardly therefrom and having a relatively narrowbottom edge, said bottom edge containing material having a greater wearresistance than the terial of said body.

3. A digger tooth including a body adapted for no horizontal travelwithin the earth having an upwardly and rearwardly directed forwardface, said body extending upwardly and rearwardly at a lesser angle tothe horizontal therefrom, and having relatively narrow side edgescontaining material having a greater wear resistance than the materialof said body.

4. A digger tooth including a body adapted for horizontal travel withinthe earth having an upward andrearwardly directed forward face, the,rearwardly extending faces of said body carrying material having agreater resistance to wear than the material of said body.

5. A digger tooth as described in claim 4 in which the material ofgreater wear resistance extends into said forward face, thereby formingworking portions of said face of said material.

6. A digger tooth as described in claim 4 in which the material ofgreater wear resistance which said body is provided with relativelynarrow side edges containing material also having a greater wearresistance than the material of said 8. A digger tooth including a bodyhaving an earth lifting face, said body extending rearwardly therefromand having a relatively narrow bottom edge, said bottom edge containingmaterial having a greater wear resistance than the material of saidbody, said wear resistant material extending into said forward facethereby forming a narrow wear resistant leading point on said face.

9. A tooth as described in claim 3 in which said wear resistant materialextends into said forward face thereby forming narrow wear resistingpoints at the sides of said face.

10. A digger point as described in claim 8 in which said body includesrelatively narrow side edges also containing material of greater wearresistance than that of said body.

11. A digger tooth including a body having an earth lifting face, saidbody extending rearwardly therefrom and having relatively narrow bottomand side edges, said edges containing material 1 ant points are ofmaterial less wear resistant than that of said edges, whereby in use thematerial will partially wear away from around said points leavingprojecting points of wear resistant material projecting from said faceat the sides and bottom thereof. I

13. A tooth as described in claim 3 in which the wear resistant materialextends into said forward face, and in' which the adjacent portions ofsaid face are less wear resistant than said material,

whereby side portions of said face will present projecting points ofwear resistant material as the tooth wears in service.

14. A digger tooth as described in claim 1 and including a rib extendingalong the upper face of body bonded thereto, .said beads being arrangedto form the edges of a triangular prismof body material, and adapted forpresentation to the formation angularly endwise.

16. A digger tooth including a body of substantially triangular sectionand prismatic formation, beads of material having a resistance to weargreater than that of the material of' said body extending along theedges thereof, the edges of said body being flattened and the wearresistant material embedded therein, the side faces of said body beingprovided with longitudinal flutes, and a longitudinal rib extendingalong the top face of said body,,and adapted for spreading the formationbeing worked in a lateral direction.

MAX M. BRODERSEN.

